MOFs-derived carbon-covered nickel phosphide for catalytic transfer hydrodeoxygenation of lignin-derived vanillin

The catalytic transfer hydrodeoxygenation (CTH) of lignin and its derivates to biofuels and fine chemicals was a promising technology for efficient utilization of biomass. Herein, a series of MOFs derived carbon-covered Ni2P@C-x catalysts were successfully fabricated via chemical vapor deposition for the CTH of lignin-derived vanillin to produce 2-methoxy-4-methylphenol (MMP). Ni2P@C-3 catalyst exhibited an excellent CTH performance, obtaining nearly 100 % conversion of vanillin and 95 % yield of MMP under the conditions of 180 °C, 3 h, and 0 MPa N2 in an isopropanol environment. Based on characterization results, the high catalytic activity of Ni2P@C-3 catalyst was attributed to Niδ+ species owing to the electron transfer from Ni to P and the P-OH groups in Ni2P phase, which provided more Lewis acid sites and Brønsted acid sites. Moreover, the small particle size with high dispersion and surface carbon defects also promoted the CTH performance. This work could provide some useful insights for the hydrodeoxygenation of lignin and its derivatives in the future.